This invention relates to stoppers made of flexible, resilient material, such as rubber or thermoplastic, for use as closures for diverse articles such as ceramic ware, art craft, shakers, piggy banks, bottles, beverage cans, thin-walled containers in general, and the like.
Stoppers of generally cylindrical form having spaced upper and lower outwardly projecting peripheral flanges or the like, and a right cylindrical outer wall portion between the flanges may be used, for example, in sealing an opening in a thin-walled container, wherein the stopper is snapped into the opening so that the flanges embrace the peripheral edge portion of the container wall defining the opening. With this arrangement, effective sealing of the opening, when required, is dependent, inter alia, upon the peripheral fit of the cylindrical wall portion of the stopper in the opening, and any discrepancies in diameter between the stopper and the opening, or any irregularities in same, may adversely affect the seal. Further, if the stopper wall portion is a tight fit in the opening, providing an effective seal, difficulty may be encountered in inserting and removing the stopper.
The present invention is directed toward providing a stopper of the kind described, in which, effective sealing in an opening is not critically dependent on the exact dimensions of the stopper and opening, so that the stopper may be fitted into over-or undersize openings, or openings with other irregularities, and which can be more easily inserted and removed.